I was assign one product in more then one category.
In one of , i was added product in Wishlist .
I want to know that this product is come for which category.
Magento Wishlist models does not contain the category details at it's tables. So you need customization for your requirement and in this case you need to use
catalog/session model to store data in session.
Mage::getSingleton('catalog/session')->getLastVisitedCategoryId() is an alternative solution for your case. I am not sure 100% about it.